This invention relates to novel compounds synthesized from polycarboxy benzene dianhydrides. More specifically, the present invention relates to compounds synthesized by reacting fluorinated or hydrocarbon pyromellitate diester-diacid chlorides with alkanols having a terminal halogen. The compounds of the present invention are useful as soil and water repelling agents.
Fluorinated pyromellitates and the use of such compounds as surface modifiers is disclosed in U.S. Pat. No. 4,209,610 (Mares et al., 1980). Mares et al. discloses various pyromellitate tetraesters wherein two ester moieties contain partially fluorinated alkyl groups and wherein two ester moieties contain alkyl groups substituted with a hydroxyl group or alkyl groups substituted with a halogen and a hydroxyl group. Mares et al. also discloses a method for applying the compounds in organic solution to various fibers. A method for applying the compounds in an aqueous emulsion is disclosed in U.S. Pat. No. 4,092,754 (Marshall et al., 1980).
We have discovered that esterifying pyromellitic dianhydride with partially fluorinated alcohols and alkanols having a terminal halogen or with hydrocarbon alcohols and alkanols having a terminal halogen results in compounds which are useful as soil and water repellents. The pyromellitates of the present invention are also expected to have improved retention characteristics when applied to various fibers as opposed to the retention characteristics of previously known compounds.